Thumbs for Side Tabs

The implementation of the thumbnails-on-hover for tabs on the right side a) covers tabs below the one on which you hovering, so that you can't see those tabs and b) bleeds off the right side of the UI unless you have other vertical element(s) placed to the right, such as bookmark panel. I think it would be a cleaner implementation if, when you hover a side tab, the thumb that pops up shows "inboard" of the tab, ie toward the center of the UI rather than dropping down. Down is perfect for top tabs, but not for side tabs.